The automatic explosion arrester for installation onto gas conveying pipeline includes one pipeline cut-off valve, and one executing mechanism on the valve body rack with gas inlet and gas outlet extending beyond the valve body and one piston rod connected to the valve core coaxial with the valve sealing surface. It features one gas generator set outside the valve body and connected to the gas inlet, one sensor set in the gas pipeline and in the location apart from the pipeline cut-off valve by 40-60 m, and one controller connected to the sensor and the gas generator. The gas generator can produce gas fast to cut off the gas conveying pipeline in very short time to avoid mine gas combustion and explosion accident.